Spirulina Sp Research Articles

English

Spirulina sp. JXSC-S1 was isolated from a local turtle breeding wastewater storage pool in Jiaxing City, Zhejiang Province, China. Morphological studies revealed that the color, shape, spiral pitch, spiral wide and cell size of the strain fits the typical morphological characteristics of Spirulina platensis. Growth dynamics of the strain were studied in both Zarrouk medium and turtle breeding wastewater (TBW), and were compared with three S. platensis strains S6, S2 and Ns-90020 that are applied in large-scale Spirulina culturing in China. All strains grew well in Zarrouk medium. The strain JXSC-S1 demonstrated a growth rate of 1.64 day-1, similar to the growth rates of S. platensis S6 and S2 and faster than S. platensis Ns-90020. When the culturing medium was changed to TBW, all the strains except the strain JXSC-S1 grew much slower than in Zarrouk meidum. By means of continuous TBW cultivation, the biomass yield of Spirulina sp. JXSC-S1 was up to 24±9 g·m-2·day-1 in dry weight, with 59.10±3.48% of crude protein in dry mass, meeting the Chinese Spirulina Standard for Animal Feed (GB/T 17423-1998). This study shows that Spirulina sp. JXSC-S1 can be used for production of aquatic protein feed by recycling nitrogen and phosphorus from TBW. Key words: Spirulina platensis, morphological identification, growth kinetics, Zarrouk, turtle breeding wastewater, aquatic protein feed.

Mono and simultaneous removal of crystal violet and safranin dyes from aqueous solutions by HDTMA-modified Spirulina sp.

The process of mono and binary removal of crystal violet and safranin dyes by Spirulina sp. (blue-green algae) modified with cationic surfactant is evaluated. The surfactant used was hexadecyltrimethylammonium bromide (HDTMA). Spirulina sp. was cultivated in Zarrouk's medium. The adsorptive properties of the modified Spirulina sp. (HDTMA-algae) were tested as a function of pH (2–10), contact time (5–180min), temperature (25–45°C), and initial dye concentrations (25–300mg/L) and characterized with FTIR, SEM, EDX, XRD and BET analyses. The specific surface area of HDTMA-algae was 0.1990m2/g. The data were fitted to non-linear Langmuir, Freundlich, and Dubinin–Radushkevich (D–R) isotherm models and non linear pseudo-first-order and pseudo-second-order kinetic models. The adsorption was 75% and 88% at pH 2 for Crystal Violet and Safranin dye, respectively. The maximum adsorption capacities were 101.87mg/g and 54.05mg/g and the kF values were 0.96L/g and 3.56L/g for Crystal Violet and Safranin, respectively. The kinetics of Crystal Violet and Safranin dyes onto HDTMA-algae were best described by the pseudo-second-order kinetic model. The negative values of free energy and enthalpy change indicated the feasibility, spontaneity, and exothermic nature of the adsorption process. Also, binary adsorption of Crystal Violet and Safranin dyes onto HDTMA-algae from binary dye mixtures is compared.

English

The atmospheric concentration of CO2, the main greenhouse gas (GHG), has increased rapidly since the beginning of the industrial age. Anthropogenic emissions from coal-fired power plants are responsible for approximately 7% (w/w) of global CO2 emissions. Microalgae CO2biofixation is a technology that reduces GHGs based on the use of solar energy through photosynthesis to capture and use the CO2 that is produced by thermal and other sources. We determined the kinetic characteristics of the cyanophyteSpirulina sp. LEB 18 and the chlorophyteScenedesmus obliquus LEB 22 and their capacities for CO2 fixation from the flue gas of a thermoelectric plant. The kinetic growth parameters of Spirulina increased when flue gas was used as the sole carbon source. At the end of cultivation, the biomass production of Spirulina sp. LEB 18 was 35% higher in the medium with flue gas compared to the Zarrouk medium, resulting in 5.7% CO2biofixation and a 24% reduction in flue gas CO2. Thus, the biofixation of CO2 from flue gas may be useful in helping to alleviate global warming. Key words: fossil fuel, microalgae, cyanophyte and chlorophyte.

Spirulina cultivation with a CO2 absorbent: Influence on growth parameters and macromolecule production

The objective of this study was to select a concentration of CO2 absorbents to supplement Spirulina sp. LEB 18 cultivation and to evaluate the effect of these compounds on the growth and production of macromolecules. Three initial biomass concentrations (X0), eight concentrations of monoethanolamine (MEA), and three NaOH concentrations were tested. The selected MEA concentrations did not inhibit the growth of Spirulina and doubled the dissolved inorganic carbon concentration in the assay medium in relation to the concentration of NaOH. The protein concentration in the biomass grown with MEA was, on average, 17% higher than that obtained with NaOH. Thus, it was found that MEA did not reduce the productivity of Spirulina sp. LEB 18, and its use can be further explored as a means for converting the carbon dissolved in the medium to biomolecules.

CO2 Biofixation by the Cyanobacterium Spirulina sp. LEB 18 and the Green Alga Chlorella fusca LEB 111 Grown Using Gas Effluents and Solid Residues of Thermoelectric Origin.

The concentration of carbon dioxide (CO2) in the atmosphere has increased from 280 to 400ppm in the last 10years, and the coal-fired power plants are responsible for approximately 22% of these emissions. The burning of fossil fuel also produces a great amount of solid waste that causes serious industrial and environmental problems. The biological processes become interesting alternative in combating pollution and developing new products. The objective of this study was to evaluate the CO2 biofixation potential of microalgae that were grown using gaseous effluents and solid residues of thermoelectric origin. The microalgae Chlorella fusca LEB 111 presented higher rate of CO2 biofixation (42.8%) (p < 0.01) than did Spirulina sp. LEB 18. The values for the CO2 biofixation rates and the kinetic parameters of Spirulina and Chlorella cells grown using combustion gas did not differ significantly from those of cells grown using CO2 and a carbon source in the culture media. These microalgae could be grown using ash derived from coal combustion, using the minerals present in this residue as the source of the essential metals required for their growth and the CO2 derived from the combustion gas as their carbon source.

English

In this research, mass production of freshwater rotifer, Branchionus calyciflorus, for aquaculture in south-eastern Nigeria, using different food types (Chlorella sp., Spirulina sp and Baker&rsquo;s yeast) was investigated. Rotifer stock culture was prepared using Nitrogen phosphorus Potassium, (NPK) + urea (50 : 2.5 g) and chicken droppings (25 g) with freshly grown alga. Different food concentrations (150, 300, 650 and 1000 mg/ml) and feeding intervals (2x and 3x per day) were used to grow B. calyciflorus in a Batch culture method. The highest population growth was attained with 650 mg/ml of Chlorella sp. (213.81&plusmn;9.94 individuals/ml), followed by Baker&rsquo;s yeast (196.67&plusmn;8.18 individuals/ml) and 300 mg/ml of Spirulina sp. (151.90&plusmn;7.98 individuals/ml). The least population growth of B. calyciflorus was recorded with 150 mg/ml concentration of Chlorella sp. and Spirulina sp. (81.43&plusmn;6.19 and 75.71&plusmn;5.12 individuals/ml, respectively), and 1000 mg/ml of Baker&rsquo;s yeast (from local market) (65.24 &plusmn;3.86 individuals/ml). The peak population growth was attained on day 8 of experiment (p &lt; 0.05). This study indicated that both the quantity and quality of food type have significant role on mass production of rotifer for aquaculture. &nbsp; Key words: Branchionus calyciflorus, mass production, aquaculture, fish farm, Nigeria.

Magneto-Conductance Effect of Natural Porphyrin Thin Films Fabricated by Spin Coated Method

We present magneto conductivity measurements in natural porphyrin thin films in magnetic fields of 100 Oe at room-temperature. The films used in this experiment were isolated from natural spirulina sp by chromatography procedure with n-hexane. Each layer fabricated by spin coater methods with rotation speed of 2500 rpm for 60 second is followed post heating at temperature of 60°C for 300 second. The procedure is repeated N times. Magneto-conductance effect is presented at room temperature with induce magnetic field in plane of films. The results show that ratio magneto-conductance decreases with the increase of voltage provided. The magneto-conductance ratio increase with the increase of N repetition number. Finally, both the results indicate that magneto-conductance effect could be realized due to annihilation of carrier charge.

English

Microalgae use photosynthesis as their principal metabolic mechanism to obtain organic carbon from the inorganic carbon contained in CO2 using solar energy. This process releases oxygen into the atmosphere. The aim of this study was to determine the most appropriate biomass concentration for growing Spirulina sp. LEB 18 (Cyanobacteria) in a vertical tubular photobioreactor with biomass removal and recycling of the medium to maximize CO2 biofixation. The maximum CO2 biofixation was obtained when the culture was maintained at 600 mg L-1 biomass concentration. Under this condition, the highest CO2 biofixation value was 186.8 &plusmn; 73.1 mg L-1 d-1, and the maximum productivity was 85.9 &plusmn; 6.0 mg L-1 d-1. &nbsp; Key words: Biofixation, carbon dioxide, microalgae, recycling, tubular photobioreactor.

Evaluation of different modes of operation for the production ofSpirulinasp.

BACKGROUND Semi-continuous microalgae cultivations are large-scale production alternatives that maintain high microorganism growth rates. Studies show that semi-continuous cultivation can be conducted in two ways. In one, a blend concentration is set for the linear phase. The other uses a time interval dilution. This present work aimed to determine which mode of semi-continuous cultivation of Spirulina sp. LEB 18 presented the best kinetic response. RESULTS For the Spirulina sp. LEB 18 cultivation, the blend concentration was 1.6 g L−1. The maximum average productivity (0.092 g L−1 d−1) and biomass amount (8.37 g) were found for the assay with blend concentration of 1.6 g L−1 and a renewal rate of 40% (v/v). CONCLUSION The best semi-continuous cultivation mode for Spirulina sp. LEB 18 used a fixed blend concentration. This work proved the importance of setting a blend concentration on a theoretical biochemical and biotechnological basis. © 2015 Society of Chemical Industry

English

In response to the environmental problems caused by plastics of petrochemical origin, a reduction in the use of these materials and their replacement by biodegradable polymers have been sought. Polyhydroxybutyrate (PHB), a biopolymer of biological origin that belongs to the polyhydroxyalkanoates (PHAs), is similar to polypropylene in terms of its mechanical properties, thermodegradability and melting temperature. Various microorganisms, including cyanobacteria, can synthesize this biopolymer. The objective of this study was to stimulate biopolymer synthesis by Spirulina sp. LEB 18 that was grown under different nutritional conditions. Initially, the growth was conducted with Spirulina sp. LEB 18 without the adaptation of the inoculum. In these assays, the concentrations of the carbon, nitrogen and phosphorus sources were varied. The assay that showed the maximum concentration of biopolymers was reproduced with the adaptation of the inoculum for 45 days. There was an inverse relationship between the cell growth and biopolymer synthesis. The assay that contained 0.25 g L-1 sodium nitrate, 4.4 g L-1 sodium bicarbonate and 0.5 g L-1 potassium phosphate showed the maximum cell concentration (0.6 g L-1) and a low biopolymer accumulation (13.4%). In addition, the assay that contained 0.05 g L-1 sodium nitrate, 8.4 g L-1 sodium bicarbonate and 0.5 g L-1 potassium phosphate produced a high biopolymer concentration (30.7%) and a low cell concentration (0.5 g L-1). The adaptation of the inoculum increased the cell concentration by 7.0% and the biopolymer yield by 20.5%. The biopolymer production was more efficient in assays in which the nitrogen was restricted and had maximum carbon consumption. Key words: Biopolymers, polyhydroxyalkanoates, microalgae, cyanobacteria.

Chemical absorption and CO2 biofixation via the cultivation of Spirulina in semicontinuous mode with nutrient recycle

The chemical absorption of carbon dioxide (CO2) is a technique used for the mitigation of the greenhouse effect. However, this process consumes high amounts of energy to regenerate the absorbent and to separate the CO2. CO2 removal by microalgae can be obtained via the photosynthesis process. The objective of this study was to investigate the cultivation and the macromolecules production by Spirulina sp. LEB 18 with the addition of monoethanolamine (MEA) and CO2. In the cultivation with MEA, were obtained higher results of specific growth rate, biomass productivity, CO2 biofixation, CO2 use efficiency, and lower generation time. Besides this, the carbohydrate concentration obtained at the end of this assay was approximately 96.0% higher than the control assay. Therefore, Spirulina can be produced using medium recycle and the addition of MEA, thereby promoting the reduction of CO2 emissions and showing potential for areas that require higher concentrations of carbohydrates, such as in bioethanol production.

Carbon dioxide sequestration in wastewater by a consortium of elevated carbon dioxide-tolerant microalgae

The emission of the green house gas (GHG) carbon dioxide (CO2) in the atmosphere at an increasingly high rate is the primary cause of global warming. A study was performed to isolate an elevated CO2-tolerant microalgal consortium (CMAC) and then characterize growth-influencing environmental factors, CO2 sequestration capacity and the potential applications of CMAC for elevated CO2 sequestration. The CMAC was isolated from a wastewater treatment plant under a selection condition consisting of 50% CO2 in air (v/v). The CMAC species were identified as Chlorella sp., Scenedesmus sp., Sphaerocystis sp. and Spirulina sp. Multiple variables including 20% CO2, culture medium pH of 8–9, and an illumination intensity of 50–80μmolm−2s−1 were found to be optimal for high density growth of CMAC for uptake of elevated CO2, although the CMAC were demonstrated to grow well in up to 50% CO2. The CMAC showed high CO2 sequestration (53–100%; 150–291mgg−1) with strong growth performance in wastewater. The lipid content of CMAC was high (350±0.31mgg−1), which gave a high biodiesel yielding capacity (420±0.43mgg−1). CMAC was also found to have high nutrient removal abilities (PO4-P, up to 59% and NH4-N, up to 39%). These characteristics all indicate that the isolated CMAC could be used as an efficient tool for biofuel generation from wastewater as well as bioremediation of pollutants. Thus by coupling the identified CO2 sequestration potential of the CMAC with the wastewater tolerance characteristics, there is novel potential to integrate wastewater treatment with CO2 sequestration and biomass utilization in order to mitigate the problems of increased GHG in response to global warming.

Investigation of pH-dependent swelling behavior and kinetic parameters of novel poly(acrylamide-co-acrylic acid) hydrogels with spirulina

AbstractPoly(acrylamide-co-acrylic acid)-spirulina (AAm-AAc-Sp) hydrogels were prepared by free radical solution polymerization of the monomer acrylamide (AAm) and the comonomer acrylic acid (AAc) with N,N-methylene bisacrylamide (BAAm) as the crosslinker in the presence of spirulina (Sp), which is a microalga species. The swelling ratios of the hydrogels were followed by gravimetric measurements. Hence, swelling kinetics and diffusion parameters were determined. Furthermore, the morphological structures and mechanical behaviors of the hydrogels were investigated by scanning electron microscopy and by using a uniaxial compression machine, respectively. All the results showed that spirulina had strong influence in the pH-dependent swelling behavior, as well as on the kinetic and diffusion parameters due to its interaction with the acrylic acid units. These interactions were attributed to spirulina, which caused a change in pore size and its distribution. The present novel hydrogels showed high swelling at neutral pH, but collapsed slowly at low and high pH values. Thus, these AAm-AAc-Sp hydrogels can be good candidates for pH-sensitive drug delivery systems.

Comparative Study of Bioactive Substances Extracted from Fresh and Dried Spirulina sp.

The increase consumption of natural substances has brought about in increasing demand on biological source, including Spirulina sp. This Spirulina sp. has been recognized to provide some natural substances such as natural colorant, source of vitamins, protein and some minerals. Different material state of Spirulina sp. in the form of fresh and dried form may cause different quantity and quality of natural substances in microalgae which posses a wide range of change including nutritional and natural substances. The aims of the study was to investigate the bioactive compounds resulted from different form of Spirulian sp (fresh and dried) quantitatively. The materials used were fresh and dried Spirulina sp which was extracted by ethanol. Analysis were subjected for phytochemical screening, flavoniod, phenolic acid and antioxidant activity (DPPH scavenging activity). The results showed that total flavonoid of fresh and dried are: 25.6615±1.62 and 110.1356±12.5 quercetin/gr extract; phenolic acid: 2.117±0.99 and 6.92±0.03 GAE/gr extract; IC50: 33.0755, respectively. Fresh sample of Spirulina platensis shows better results in bioactive compounds quantitatively and qualitatively compared to that of dried sample, and drying process at 40-50oC does not give any significant different on nutritional quality of dried sample of Spirulina platensis compared to fresh samples.

Combination of Spirulina with glycyrrhizin prevents cognitive dysfunction in aged obese rats.

Objectives:To evaluate the cognition enhancing effect of the combination of Spirulina and glycyrrhizin in monosodium glutamate (MSG)-induced obese aged rats.Materials and Methods:Obesity was induced in rats by administration of MSG (intraperitoneally, 4 mg/g body weight) for 14 consecutive days from day 1 after birth. Subsequently, the animals were allowed to grow for 18 months with food and water ad libitum. Hypercholesterolemia, hyperglycemia, leptin resistance, were monitored in these animals. Cognitive status was assessed by Barne's maze task and hippocampal acetylcholinesterase (AChE) levels. Further, the animals were treated with Spirulina (Sp) (oral route, 1 g/Kg body weight, for 30 days) alone or glycyrrhizin (Gly) alone (intraperitoneal route, 0.1 mg/Kg, on day 15 and day 21), or their combination (SpGly). Counting of the treatment days was done by considering first day of Sp administration as day 1. After the completion of 30 days of Spirulina treatment or 2 doses of Gly administration or the combination (SpGly) treatment, the animals were left for 3 weeks. They were then were assessed for their biochemical and cognitive changes.Results:The combination of Sp with Gly showed a significant reduction (P < 0.0001) in glucose, cholesterol, leptin levels in the serum with improvement in cognitive functions with concomitant reduction in AChE activity in the hippocampal tissue homogenates (P < 0.0001) of the obese rats.Conclusion:SpGly combination has a potential role in reversing cognitive dysfunctions associated with aging and obesity.

Inhibition of Fusarium graminearum growth and mycotoxin production by phenolic extract from Spirulina sp.

Fusarium graminearum is a fungal species complex pathogenic occurring worldwide, mainly associated with cereal crops. The most important Fusarium mycotoxins are fumonisins, zearalenone and trichothecenes. The availability of efficient control measures that are less harmful to both the environment and the consumers is urgent. For such, phenolic acids (PAs) from natural sources are known to reduce fungal contaminations. This work aimed to identify the PAs present in a culture extract of Spirulina algae (strain LEB-18) and evaluate its effect on mycelial growth rate, glucosamine level, amylase activity and mycotoxin production by four strains of two lineages of F. graminearum. Results showed that amendment of potato dextrose media with LEB-18 extract (3% w/v), which was mainly composed by gallic acid, greatly reduced radial growth of fungal colonies compared to media containing a single PA and the control. Also, average reductions of 40% and 62% in the glucosamine levels and the amylase activity were observed. In general, the LEB-18 extract and the PAs reduced mycotoxin concentration, with an average reduction of 68% for the trichothecene mycotoxins deoxynivalenol and nivalenol.

Biosorption of chromium by using Spirulina sp.

Presence of heavy metals in the aquatic system is posing serious problems and chromium has been used in many industries and the removal of chromium ions from waste waters is significant. Biosorption is one of the economic methods that is used for the removal of heavy metals. In the present study, the biomass generated from the dried Spirulina sp. was used for evaluating the biosorption characteristics of chromium ions in aqueous solutions. Batch adsorption experiments were performed on these leaves and it was found that the amount of metal ions adsorbed increased with the increase in the initial metal ion concentration. In this study effect of agitation time, initial metal ion concentration, temperature, pH, and biomass dosage were studied. Maximum metal uptake was observed at pH=5. Maximum metal uptake (qmax) was 90.91mg/g .The biosorption followed both Langmuir and Freundlich isotherm models but the Freundlich isotherm model was better than the Langmuir with R2=0.997. The adsorption equilibrium was reached in about 1h. The kinetics of biosorption followed the second-order rate. The biomass could be regenerated using 0.1M HNO3. FTIR Spectrums of biomasses revealed the presence of hydroxyl, amino, carboxylic and carbonyl groups. The scanning electron micrograph clearly revealed the surface texture and morphology of the biosorbent.

Modelamiento matemático y por redes neuronales artificiales del crecimiento de Spirulina sp. en fotobiorreactor con fuente de luz fluorescente e iluminación en estado sólido

The Gompertz and logistic mathematical models in the Spirulina sp. growth kinetics were evaluated and were compared with a modeling through Backpropagation Artificial Neural Networks (BP- ANN). Spirulina was cultivated in a (3 L/min) of 500 mL aerated laboratory photobioreactor with 40W fluorescent lighting and 1W lighting Solid State (LED-Light Emitting Diode) obtaining 11.0 klx lighting with both systems. The LED lighting allowed to obtain a (ɑ) 0.90 high biomass value compared with that one obtained with fluorescent lighting of 0.82, as well as a greater growth rate μ=0.63 h-1 preceded by a shorter latency time λ = 0.34 h. The BP-ANN showed a good accuracy with respect to the Gompertz I corrected model for both the Spirulina sp cultivation case with fluorescent lighting and with LED displaying correlation coefficients (R) of the 0.993 and 0.994 order respectively, with regard to the experimental data. Spirulina modeling through the Gompertz I corrected model is advantageous because besides showing R 0.987 and 0.990 values in Spirulina sp. cultures with fluorescent lighting and with LED respectively, it allows to attain the growth parameters kinetics directly.

Kinetic studies on the biosorption of phenol by nanoparticles from Spirulina sp. LEB 18

A kinetic study on the biosorption of phenol by nanoparticles from Spirulina sp. LEB 18 was carried out. The Spirulina sp. nanoparticles were prepared and characterized. Kinetic curves of phenol biosorption were obtained in batch system, being verified the effects of initial concentration (50, 150, 250 and 450mgL−1) and stirring rate (50, 200 and 400rpm). The models of pseudo-first order, pseudo-second order, Elovich, Bangham, general order and Weber–Morris were used for the kinetic interpretations. Spirulina sp. nanoparticles were stable, monodisperse, spherical with mean diameter of 230nm. The phenol biosorption was a relatively fast process, being favored at higher values of initial concentration and stirring rate. Pseudo-second order and general order models showed satisfactory fit with the experimental data and the maximum biosorption capacity was around 101mgg−1. From the Weber–Morris analysis, it was found that external mass transfer and intraparticle diffusion occurred during the phenol biosorption on Spirulina sp. nanoparticles. The external mass transfer was faster at higher values of initial concentration and stirring rate, and the intraparticle diffusion was favored at high initial concentrations.

Effect of copper and lead on two consortia of phototrophic microorganisms and their capacity to sequester metals

The roles of consortia of phototrophic microorganisms have been investigated in this paper to determine their potential role to tolerate or resist metals and to capture them from polluted cultures. With this purpose, two consortia of microorganisms: on one hand, Geitlerinema sp. DE2011 (Ge) and Scenedesmus sp. DE2009 (Sc) (both identified in this paper by molecular biology methods) isolated from Ebro Delta microbial mats, and on the other, Spirulina sp. PCC 6313 (Sp) and Chroococcus sp. PCC 9106 (Ch), from Pasteur culture collection were polluted with copper and lead. In order to analyze the ability of these consortia to tolerate and capture metals, copper and lead were selected, because both have been detected in Ebro Delta microbial mats.The tolerance-resistance to copper and lead for both consortia was determined in vivo and at cellular level by Confocal Laser Scanning Microscopy (CLSM-λscan function). The results obtained demonstrate that both consortia are highly tolerant-resistant to lead and that the limits between the copper concentration having cytotoxic effect and that having an essential effect are very close in these microorganisms.The capacity of both consortia to capture extra- and intracellular copper and lead was determined by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) respectively, coupled to an Energy Dispersive X-ray detector (EDX). The results showed that all the microorganisms assayed were able to capture copper extracellularly in the extrapolymeric substances, and lead extra- and intracellularly in polyphosphate inclusions. Moreover, the studied micro-organisms did not exert any inhibitory effect on each other's metal binding capacity.From the results obtained in this paper, it can be concluded that consortia of phototrophic microorganisms could play a very important role in biorepairing sediments polluted by metals, as a result of their ability to tolerate or resist high concentrations of metals and to bioaccumulate them, extra- and intracellulary.